Results 71 to 80 of about 1,091,898 (247)
Shuitu Baochi Xuebao, 2016 采集广东省主要成土母质（玄武岩、砂页岩、第四纪红土和花岗岩）发育的林地、耕地和园地土壤剖面各发生层土壤，测定了土壤颗粒组成、有机质、CEC等理化性质，探讨了不同母质发育土壤颗粒分布的分形维数特征及其与土壤理化性质的关系。结果表明，玄武岩、第四纪红土、花岗岩和砂页岩发育土壤分形维数变幅分别为2.923 9～2.981 2，2.858 8～2.937 7，2.769 3～2.923 1和2.544 6～2.885 6；玄武岩和第四纪红土发育土壤颗粒分布分形维数与砂页岩发育土壤存在显著差异 ...
姜 坤 +5 more
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, 2008 应用土壤颗粒的重量与粒径分布原理来描述了古尔班通古特沙漠地风沙土壤颗粒的分形特征。通过对10种样品颗粒的机械组成进行分析,分别计算出了它们的分形维数(D=2.3237～2.9347),并分析了其与流动风沙土、半固定风沙土和固定风沙土之间的关系。分析结果表明,风沙土壤结构具有明显的分形特征,其粒径分布分形维数为2～3。土粒表面分形维数与2～0.2mm间的土粒含量存在显著的负相关;而与0.02～0 ...
陶辉, 苏里坦, 宋郁东
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Coalition Breakdown and Subsystem Exit
Policy Studies Journal, EarlyView.ABSTRACT Why actors choose to work together (or not) to advance policy has been the central area of inquiry within the Advocacy Coalition Framework (ACF). Existing research has mainly emphasized the pathway towards coalition formation and evolution, underscoring the stable patterns of allies and opponents observable in policy processes over a decade or
Charlie F. Thompson
wiley +1 more source
Gaoya dianqi, 2001 本文将分形理论应用于局部放电模式识别 ,从统计图谱中提取分形特征。在局部放电模式试验基础上 ,采用计盒数的分形维数算法 ,从大量的局部放电样本中提取分形网格维数特征参数 ,提高了局部放电模式的准确性。
李剑 +4 more
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, 1994 现场和实验室观察表明;在断裂区内的雁型裂纹具有一个Ｒｉｅｄｅｌ几何结构。本文应用剪切裂纹位错堆积（Ｐｉｌｅ－ｕｐ）模型;描述了雁型裂纹形成的拉破坏机理;建立了雁型裂纹的分形模型来模拟Ｒｉｅｄｅｌ几何结构。根据这个模型;可以直接量测出现场和实验中出现的雁型裂纹的分形维数。在此基础上;应用分形损伤演化模型;推导出了雁型裂纹的能量耗散 ...
谢和平
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Climate change and crop resilience: harnessing metabolomics for predicting stress tolerance
New Phytologist, Volume 251, Issue 3, Page 975-995, August 2026.Summarised methodology for metabolite biomarker discovery and genomic targets selection for those metabolites to predict high‐throughput phenotypic and agronomic traits of interest for direct uptake in breeding programmes. Summary Global warming is driving climate change to levels not experienced since the advent of agriculture, primarily due to ...
Agyeya Pratap +3 more
wiley +1 more source
, 1998 应用非线性科学中的分形几何理论，以黄淮海平原封丘试区的芦苇为例，研究芦苇生长格局的分形特征。计算表明，芦苇大小分布的分形维数在0．6235—0．8761之间。统计分析表明，其分布格局可明显地分为两个时期：在芦苇生长的初期，其大小分布较为均匀（分维＞0.8），而在芦苇生长的中后期（6月底以后），大小分布差异较大（分维＜0.7）
蔡庆华,赵斌,潘文斌
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New Phytologist, Volume 251, Issue 3, Page 1127-1142, August 2026.Schematic representation of the causal sequence through which rapid water loss imposes diffusive and nondiffusive restrictions on carbon assimilation. Summary Drought is an abnormally prolonged water deficit posing major challenges to plants. Stomatal closure has long been considered the primary factor limiting photosynthesis during the early stages of
Chandra Bellasio +4 more
wiley +1 more source
Gaoya dianqi, 2019 电力变压器绕组受短路电磁力作用后,可能出现可恢复的弹性变形或不可恢复的塑性变形。文中通过电磁-结构耦合有限元分析,对短路电流冲击作用下的变压器绕组弹、塑性变形特性进行理论分析和三维数值模拟,以揭示绕组弹性和塑性变形机理。首先通过有限元电磁计算分析了绕组内部短路电磁力分布,其中绕组线饼的周向电磁力分布不均是导致绕组变形的重要原因。在弹性变形计算的基础上,依据材料学的弹塑性变形分析理论,构建了绕组累积变形的量化分析模型,能够反映多次短路电磁力作用后绕组变形的累积效应。最后,以一台110 kV/25 000 ...
张海军 +4 more
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